For the past week or so I have been getting multiple instances of the following event log error:

Event ID:	39510
Event type:	Error
Event time:	8/15/2011 2:32:58 PM
Source:	Scheduler
Event code:	RUN
IP address:	
 	
Description:	Message: Thread was being aborted. 
Stack Trace: 
at System.Threading.Thread.SleepInternal(Int32 millisecondsTimeout)
at CMS.Scheduler.SchedulingTimer.Run()
 	
Machine name:	GONZO
Event URL:	
URL referrer:	
User agent:

In every case the error immediately follows the Application_End ENDAPP event.

I do a have few custom scheduled tasks that I'm executing, but nothing out of the ordinary and they have been running just fine for the past few weeks/months. When I think back to what I may have changed around the time the errors showing showing up the only thing that comes to mind is setting the following in the web.config:

<!-- Scheduler -->
<add key="CMSUseAutomaticScheduler" value="true" />
<add key="CMSRunSchedulerWithinRequest" value="false" />

Anybody have an idea as to what's happening here?